Archimedes’ Principle: Made EASY | Physics

Summary

This video explains Archimedes' Principle, which states that a body immersed in a fluid experiences an upward force equal to the weight of the displaced fluid. Through experiments with a ball in water, the video demonstrates how objects feel lighter in water due to this upward force, known as buoyant force. The video simplifies complex concepts, introduces a helpful mnemonic to remember the principle, and explains its applications in both fully and partially submerged objects. Viewers are encouraged to experiment and reflect on how this principle applies when swimming or interacting with fluids.

Takeaways

• 😀 Archimedes' principle explains why objects feel lighter in water than in air.
• 😀 The principle is why a small steel coin sinks, but a massive steel ship can float.
• 😀 Fluids, including liquids and gases, exert an upward force on objects immersed in them.
• 😀 Archimedes' principle states that the upward force on an object is equal to the weight of the fluid displaced by the object.
• 😀 The upward force is also called buoyant force or upthrust, which is easy to observe with objects in water.
• 😀 The difference between an object's weight in air and water is the apparent weight, which indicates the upward force acting on the object.
• 😀 A simple experiment with a ball in water demonstrates how to measure the upward force using a spring balance.
• 😀 The weight of the water displaced by an object in water is equal to the upward force exerted on the object.
• 😀 Archimedes' principle applies not only to fully immersed objects but also to partially immersed objects.
• 😀 The formula for calculating the upward force is based on the volume of displaced fluid, its density, and gravitational acceleration.
• 😀 A mnemonic to remember Archimedes' principle: 'Up = World' – meaning upward force equals the weight of displaced liquid.

Q & A

What is Archimedes' principle?

Archimedes' principle states that when a body is fully immersed in a fluid, it experiences an upward force that is equal to the weight of the fluid displaced by it.

Why does a body feel lighter in water compared to when it's in the air?

A body feels lighter in water due to the upward force exerted by the water, which is also known as buoyant force or upthrust.

How can we measure the upward force acting on an object submerged in water?

The upward force can be measured by observing the difference between the object's weight in air (real weight) and its weight in water (apparent weight). The difference gives the upward force.

What is the real weight and apparent weight of an object in water?

The real weight is the weight of the object in air, and the apparent weight is the weight of the object when submerged in water. The difference between these two weights represents the upward force exerted by the water.

What is the mnemonic to remember Archimedes' principle?

The mnemonic to remember Archimedes' principle is 'Up World Force,' where 'Up' stands for upward force and 'World' stands for the weight of the liquid displaced.

How is the volume of displaced liquid related to the upward force?

The upward force is directly proportional to the volume of the liquid displaced. It can be calculated using the formula: Upward Force = Volume of liquid displaced * Density of liquid * Gravitational acceleration (V * D * G).

What is the difference between Archimedes' principle for completely and partially submerged objects?

Archimedes' principle works for both completely and partially submerged objects. In both cases, the upward force is equal to the weight of the liquid displaced.

What role does buoyancy play in swimming?

Buoyancy, caused by the upward force of the water, helps keep a swimmer afloat and allows for swimming. It is the reason why a swimmer can float and move in the water.

Why does a steel ship float, but a small steel coin sinks in water?

A steel ship floats because it displaces a large volume of water, creating enough upward force to counteract its weight. A small steel coin sinks because it displaces less water, and the upward force is not enough to support its weight.

What does Archimedes' principle explain in practical terms during swimming?

In practical terms, Archimedes' principle explains why a swimmer feels lighter in the water and can float. The buoyant force exerted by the water allows them to stay afloat and makes it easier to swim.